Product Description: As rising levels of mercury in the environment pose an increasing threat of toxicity to humans and wildlife, several laws already call for industries to reduce mercury emissions at the source. Ecosystem Responses to Mercury Contamination: Indicators of Change outlines the infrastructure and methods needed to measure, monitor, and regulate the concentration of mercury present in the environment...read more

Explains how to operate a typewriter and provides lessons and practice drills on cassette and in printed form